整理 NixOS 配置：面向 i7-12700F + RTX 4060 的模块化桌面配置

从当前 /etc/nixos 拆出 common/plasma/中文/应用/打印模块，新增 NVIDIA 独显支持，并去掉原机硬件 UUID。

modules/nvidia.nix

@@ -0,0 +1,29 @@
+# i7-12700F 无核显，RTX 4060 独显直出
+{ config, pkgs, ... }:
+
+{
+  services.xserver.videoDrivers = [ "nvidia" ];
+
+  hardware.graphics = {
+    enable = true;
+    enable32Bit = true;
+  };
+
+  hardware.nvidia = {
+    modesetting.enable = true;
+    # 桌面机一般关 finegrained；需要休眠再开 powerManagement.enable
+    powerManagement.enable = false;
+    powerManagement.finegrained = false;
+    # Ada (40 系) 推荐开源内核模块；若黑屏可改 open = false
+    open = true;
+    nvidiaSettings = true;
+    package = config.boot.kernelPackages.nvidiaPackages.stable;
+  };
+
+  # Wayland + NVIDIA
+  boot.kernelParams = [ "nvidia_drm.fbdev=1" ];
+
+  environment.systemPackages = with pkgs; [
+    nvtopPackages.nvidia
+  ];
+}